The Psyche SPICE Data Archive
========================================================================
Last update: September 23, 2025
Introduction
============
This document describes the Psyche SPICE archive, containing
observation geometry and other ancillary data in the form of SPICE
System kernel files for the Psyche spacecraft and its instruments and
structures. It describes the archive directory structure, kernels
included in the archive, their naming conventions, and provides
pointers to the SPICE software and documentation.
Table of Contents
=================
Introduction
Table of Contents
Overview
Errata
Archive Contents
Kernel Types
Archived Kernel Details
SPK Files
PCK Files
IK Files
CK Files
LSK Files
SCLK Files
FK Files
DSK Files
MK Files
Miscellaneous Files
Checksum Files
File Formats
SPICE Software and Documentation
Contact Information
Cognizant Persons
Overview
========
This archive includes the complete set of the Psyche Mission data
files (kernel files), which can be accessed using SPICE software.
The SPICE data contain geometric and other ancillary information
needed to recover the full value of science instrument data. In
particular SPICE kernels provide spacecraft and planetary
ephemerides, spacecraft and instrument orientation, instrument
mounting alignments, and data needed for relevant time conversions.
Data in the SPICE kernel files must be accessed using the software
called the SPICE Toolkit produced and distributed by the Navigation
and Ancillary Information Facility (NAIF) Node of the Planetary Data
System.
This archive includes data covering from Psyche launch, 2023-10-13,
through the end time of the latest spacecraft orientation file
supplied in the archive. Until the end of the spacecraft lifespan
this archive will be accumulating with new data added according to
the project archiving plan.
Back to Table of Contents
Errata
======
1. This document is a simple HTML document. Providing documents in a
simple mark-up format was allowed by earlier versions of the PDS4
Standards but became prohibited in later versions starting summer
2015. Since using HTML documents was compliant at the time when a
similar document was first provided in the MAVEN PDS4 archive and
since NAIF strives to make bundle description document format and
style consistent across all archives, this document continues
to exist in this archive as an HTML document.
Back to Table of Contents
Archive Contents
================
Files in this archive are organized into a set of subdirectories
below the top-level directory. The following diagram shows the
structure and content of these directories. The directory names are
enclosed in square brackets ([]).
[top-level-directory]
|
|- bundle_psyche_spice_v*.xml Bundle PDS4 label, one or more versions.
|- readme.txt Bundle top-level readme file.
|
|-[spice_kernels] Directory containing SPICE kernels.
| |
| |- collection_spice_kernels_v*.xml PDS4 labels for Spice Kernels collections.
| |- collection_spice_kernels_inventory_v*.tab
| | Spice Kernels collections' inventories.
| |
| |-[ck] Directory containing CK files.
| | |
| | |-- *.bc Binary CK files.
| | +-- *.xml PDS4 labels for CK files.
| |
| |-[dsk] Directory containing DSK files.
| | |
| | |-- *.bds Binary DSK files.
| | +-- *.xml PDS4 labels for DSK files.
| |
| |-[fk] Directory containing FK files.
| | |
| | |-- *.tf Text FK files.
| | +-- *.xml PDS4 labels for FK files.
| |
| |-[ik] Directory containing IK files.
| | |
| | |-- *.ti Text IK files.
| | +-- *.xml PDS4 labels for IK files.
| |
| |-[lsk] Directory containing LSK files.
| | |
| | |-- *.tls Text LSK files.
| | +-- *.xml PDS4 labels for LSK files.
| |
| |--[mk] Directory containing MK files.
| | |
| | |-- *.tm Text Meta-kernel files.
| | +-- *.xml PDS4 labels for MK files.
| |
| |-[pck] Directory containing PCK files.
| | |
| | |-- *.tpc Text PCK files.
| | +-- *.xml PDS4 labels for PCK files.
| |
| |-[sclk] Directory containing SCLK files.
| | |
| | |-- *.tsc Text SCLK files.
| | +-- *.xml PDS4 labels for SCLK files.
| |
| +-[spk] Directory containing SPK files.
| |
| |-- *.bsp Binary SPK files.
| +-- *.xml PDS4 labels for SPK files.
|
|-+-[miscellaneous] Directory miscellaneous files.
| |
| |- collection_miscellaneous_v*.xml PDS4 labels for miscellaneous collections.
| |- collection_miscellaneous_inventory_v*.tab
| | Miscellaneous collections' inventories.
| |
| +-[checksum] Directory containing checksum files.
| |
| |-- *.tab Text checksum files.
| +-- *.xml PDS4 labels for checksum files.
|
+-[document] Directory containing documents.
|
|- collection_document_v*.xml PDS4 labels for document collections.
|- collection_document_inventory_v*.tab
| Document collections' inventories.
|
|- spiceds_v*.html This file and its other versions.
+- spiceds_v*.xml PDS4 labels for this file and its other versions.
Back to Table of Contents
Kernel Types
============
Different SPICE kernel types are used to store different kinds of
ancillary data.
SPK (Spacecraft Planet Kernel) files contain ephemerides (position
and velocity) for spacecraft, planets, satellites, comets and
asteroids as well as for moving or fixed spacecraft and instrument
structures. SPK files are located under the spice_kernels/spk
directory of this archive.
PCK (Planetary Constants Kernel) files contain certain physical,
dynamical and cartographic constants for target bodies, such as size
and shape specifications, and orientation of the spin axis and prime
meridian. PCK files are located under the spice_kernels/pck
directory of this archive.
IK (Instrument Kernel) files contain instrument parameters relevant
for computing an instrument's geometry such as field-of-view
definitions, CCD and optical distortion characteristics, and internal
timing parameters. IK files are located under the spice_kernels/ik
directory of this archive.
CK (C-matrix Kernel) files contain time varying orientations for
spacecraft, spacecraft structures, and articulating science
instruments. CK files are located under the spice_kernels/ck
directory of this archive.
LSK (Leapseconds Kernel) files contain the leapseconds and the
values of other constants required to perform a transformation
between Universal Time Coordinated (UTC) and Ephemeris time (ET),
which is also known as Barycentric Dynamical Time (TDB). LSK
files are located under the spice_kernels/lsk directory of
this archive.
SCLK (Spacecraft Clock Kernel) files contain on-board clock
calibration data required to perform a transformation between
Ephemeris time (ET) and spacecraft on-board time (SCLK). SCLK files
are located under the spice_kernels/sclk directory of this
archive.
FK (Frame definitions Kernel) files contain information required to
define reference frames, sources of frame orientation data and
connections between these frames and other frames supported within
the SPICE system. The science instrument frame definitions provided
in the FK files include mounting alignment information for the
instruments. FK files are located under the spice_kernels/fk
directory of this archive.
DSK (Digital Shape Kernel) files contain detailed shape models for
extended objects such as planets, natural satellites, asteroids, and
comet nuclei. DSK files are located under the spice_kernels/dsk
directory of this archive.
MK (Meta-Kernel) files list sets of related SPICE kernels that
should be used together, providing an easy way to make data from
these kernel sets available to a SPICE-based application by loading
meta-kernels into the program using the high level SPICE data loader
routine FURNSH. MK files are located the spice_kernels/mk
directory of this archive.
Archived Kernel Details
=======================
The subsections below provide details, such as file naming
conventions and specific details, for each of the kernel types
included in this archive.
Back to Table of Contents
SPK Files
SPK (Spacecraft Planet Kernel) files contain ephemerides (position
and velocity) for spacecraft, planets, satellites, comets and
asteroids as well as for moving or fixed spacecraft and instrument
structures.
This archive includes binary SPK files containing the following
kinds of ephemeris data:
- planetary ephemeris SPKs
These SPKs contain ephemeris data for the Solar System
planet barycenters, and Sun, Mercury, Venus, Earth, and
Moon, determined by the JPL Solar System Dynamics group and
are named DEXXX, e.g. DE440.
- Martian satellite ephemeris SPKs
These SPKs contain ephemeris data for Mars, Phobos, Deimos,
Sun, Earth barycenter, and Earth, determined by the
JPL Solar System Dynamics group and are named MARXXX, e.g.
MAR097.
- Psyche spacecraft SPK relative to the sun and target bodies
These SPKs contain position and velocity of the Psyche spacecraft
relative to the Sun and target bodies (when applicable) in the
J2000 reference frame. They include ephemerides for target bodies
(when applicable). These SPKs provide reconstructed data.
- Psyche DSOC ground station SPKs
These SPKs contain Earth locations of optical telescopes that
participated in the Psyche DSOC instrument. They provide general
(non-exact) telescope site locations that were deemed suitable
for the DSOC experiment.
- Psyche structures SPK
These SPKs contain relative locations of selected Psyche Spacecraft
structures and science instruments.
The SPK files are provided under the spice_kernels/spk
directory and are named according to the following schemes:
- planetary ephemeris SPKs
deVVVs.bsp
where
VVV is the ephemeris version.
- Martian satellite ephemeris SPKs
marVVVs.bsp
where
VVV is the ephemeris version.
- Psyche spacecraft SPK relative to the sun and target bodies
psyche_rec_START-END_DELIVERY_vV.bsp
where
START is the start of the file coverage in YYMMDD format.
END is the end of the file coverage in YYMMDD format.
DELIVERY is the file ops delivery date in YYMMDD format.
V is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
- Psyche DSOC ground station SPKs
psyche_dsoc_STATION_vV.bsp
where
STATION is the DSOC Ground Station abbreviation:
helmos: Helmos Aristarchos Telescope
kyroneri: Kryoneri Telescope
octl: Optical Communications Telescope Laboratory
palomar: Palomar Observatory Hale Telescope
V is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
- Psyche structures SPK
psyche_struct_vVV.bsp
where
VV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
The most detailed description of the data in each SPK file is
provided in metadata included inside the comment area of the file.
This information can be viewed using the utility program COMMNT
included in the NAIF Toolkit.
Back to Table of Contents
PCK Files
PCK (Planetary Constants Kernel) files contain certain physical,
dynamical, and cartographic constants for target bodies, such as
size and shape specifications, and orientation of the spin axis and
prime meridian.
This data set includes PC-Kernel files containing planetary
constants values used by Psyche project during the mission.
- generic text PCKs
These PCKs contain data from the reports of the IAU Working
Group on Cartographic Coordinates and Rotational Elements.
The generic text PCK version 00010 contains data from the IAU
2009 report. Produced by NAIF, JPL.
- Psyche text PCKs
These PCKs contain the rotational and ellipsoidal shape constants
for the asteroid 16 Psyche.
- Earth high-precision binary PCKs
These PCKs contain "high-precision" data giving the orientation
of the Earth as a function of time for a specified interval.
The PCK files are provided under the spice_kernels/pck
directory and are named according to the following scheme:
- generic text PCKs
pckVVVVV.tpc
where
VVVVV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
- Psyche text PCKs
psyche_vVV.tpc
where
VV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
- Earth high-precision binary PCKs
earth_SDAT_EDAT_PDAT.bpc
where
SDAT is the file's coverage start time in YYMMDD format
EDAT is the file's coverage end time in YYMMDD format
PDAT is the date from which the information contained
in the file corresponds to predicted data. Any data
prior to this date corresponds to actual measurements.
The most detailed description of the data in a text PCK file is
provided in metadata included inside the description area of the
file. This information can be viewed using any text editor program.
Back to Table of Contents
IK Files
IK (Instrument Kernel) files contain instrument parameters relevant
for computing an instrument's observation geometry such
field-of-view definitions, CCD and optical distortion
characteristics, and internal timing parameters.
This dataset contains I-kernel files for the Psyche spacecraft structures
(star trackers, solar sensors, antennas, solar arrays, DSOC base and optics)
and instruments (Gamma-ray and Neutron Spectrometer (GRNS), Magnetometer,
and Multispectral Imager (PMI)).
The IK files are provided under the spice_kernels/ik
directory and are named according to the following scheme:
- Psyche Instrument IKs
psyche_NAME_vVV.ti
where
NAME is the name of the Psyche Instrument:
grns - Psyche Gamma Ray and Neutron Spectrometer
(GRNS)
mag - Psyche Magnetometer (MAG)
imager - Psyche Multispectral Imager (PMI)
VV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
- Structures IK
psyche_struct_vVV.ti
where
VV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
The most detailed description of the data in a text IK file is
provided in metadata included inside the description area of the
file. This information can be viewed using any text editor program.
Back to Table of Contents
CK Files
CK (C-matrix Kernel) files contain time varying orientations for
spacecraft, articulating spacecraft structures, and articulating
science instruments.
The Psyche C-kernels provide the transformations between various frames
defined and used by the project.
This archive includes binary CK files containing the following kinds
of orientation data:
- Psyche Reconstructed Spacecraft Orientation CK
- Psyche Reconstructed Electric Propulsion Gimbal Orientation CK
- Psyche Reconstructed Solar Array Orientation CK
The CK files are provided under the spice_kernels/ck
directory and are named according to the following scheme:
- Psyche Reconstructed Spacecraft Orientation CK
psyche_sc_rec_START_STOP.bc
where
START is the start of the file coverage in YYMMDD format.
END is the end of the file coverage in YYMMDD format.
- Psyche Reconstructed Electric Propulsion Gimbal Orientation CK
psyche_ep_rec_START_STOP.bc
where
START is the start of the file coverage in YYMMDD format.
END is the end of the file coverage in YYMMDD format
- Psyche Reconstructed Solar Array Orientation CK
psyche_sa_rec_START_STOP.bc
where
START is the start of the file coverage in YYMMDD format.
END is the end of the file coverage in YYMMDD format.
NOTE - Psyche CKs do not include a version number in the filename.
When the CKs are created during operations, they are overwritten
in-place daily for the week in which they cover and the week
following. They are then overwritten one final time at a delay of
two weeks and those are the final CK files included in the archive.
This convention was adopted from the DAWN mission.
The most detailed description of the data in each CK file is
provided in metadata included inside the comment area of the file.
This information can be viewed using the utility program COMMNT
included in the NAIF Toolkit.
Back to Table of Contents
LSK Files
LSK (Leapseconds Kernel) files contain the leapseconds and the
values of other constants required to perform a transformation
between Universal Time Coordinated (UTC) and Ephemeris time (ET),
also known as Barycentric Dynamical Time (TDB).
This archive includes generic text LSK files produced by NAIF,
containing leapsecond information based on the IERS announcements.
The generic text LSK version 0012 contains leap second data up to
and including the December 31, 2016 leapsecond.
The LSK files are provided under the spice_kernels/lsk
directory and are named according to the following scheme:
- generic text LSKs
naifVVVV.tls
where
VVVV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
The most detailed description of the data in a text LSK file is
provided in metadata included inside the description area of the
file. This information can be viewed using any text editor program.
Back to Table of Contents
SCLK Files
SCLK (Spacecraft Clock Kernel) files contain on-board clock
calibration data required to perform a mapping between Ephemeris
time (ET) and spacecraft on-board time (SCLK).
This archive includes text SCLK files containing the following kinds of
data:
- Psyche on-board clock correlation SCLKs
This archive includes text SCLK files containing correlation data
for the main Psyche on-board clock, created by NAIF from the
SCLK_SCET files.
The SCLK files are provided under the spice_kernels/sclk
directory and are named according to the following scheme:
- Psyche on-board clock correlation SCLKs
psyche_255_sclkscet_VVVVV.tsc
where
VVVVV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
The most detailed description of the data in a text SCLK file is
provided in metadata included inside the description area of the
file. This information can be viewed using any text editor program.
Back to Table of Contents
FK Files
FK (Frame definitions Kernel) files contain information required to
define reference frames, sources of frame orientation data and
connections between these frames and other frames supported within
the SPICE system. The science instrument frame definitions provided
in the FK files include mounting alignment information for the
instruments.
This archive includes text FK files defining reference frames for
the Psyche spacecraft, its structures, and science instruments as well
as dynamic frames of interest to Psyche investigations and topocentric
frames at the sites of the telescopes participating in the DSOC experiment.
This FK was produced by NAIF using the spacecraft and instrument
design documentation as well as actual instrument alignment values
determined pre-launch and as the result of in-flight calibrations.
The FK files are provided under the spice_kernels/fk
directory and are named according to the following scheme:
- Psyche mission FK files
psyche_fk_vVV.tf
where
VV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
The most detailed description of the data in a text FK file is
provided in metadata included inside the description area of the
file. This information can be viewed using any text editor program.
Back to Table of Contents
DSK Files
DSK (Digital Shape Kernel) files contain detailed shape models for
extended objects such as planets, natural satellites, asteroids, and
comet nuclei.
This archive includes binary DSK files containing digital shape data
for the Psyche mission target asteroid 16 Psyche.
The DSK files are provided under the spice_kernels/dsk
directory and are named according to the following scheme:
- asteroid 16 Psyche DSK files
psyche_TEAM_RES_AREA_vV.bds
where
TEAM is the team responsible for producing the
model, e.g. "mdn", etc..
RES is the resolution, e.g. "icq512" for Gaskell
model (with Q=512, "m100" for 100 meter resolution).
AREA (optional) only applicable for local coverage DSKs.
Provided in the format 'mnlmxlmntmxt':
'mnl' is the minimum longitude
'mxl' is the maximum longitude
'mnt' is the minimum latitude
'mxt' is the maximum latitude
V is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
- pre-arrival asteroid 16 Psyche DSK file based on Shepard et al, 2021
shape model
psyche_shepard2021_k003_vV.bds
where
V is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
NOTE - This naming schema was used before a more formal
schema was agreed upon by the mission and is an
exception in the archive.
The most detailed description of the data in each DSK file is
provided in metadata included inside the comment area of the file.
This information can be viewed using the utility program COMMNT
included in the NAIF Toolkit.
Back to Table of Contents
MK Files
Meta-kernel (MK) files (a.k.a 'furnsh' files) provide lists of the
archived kernels included in this archive suitable for loading into
a SPICE-based application via the high level SPICE data loader
routine FURNSH. Using meta-kernels makes it easy to load with
one call a comprehensive SPICE data collection for a given period.
The text MK files are provided under the spice_kernels/mk
directory and are named according to the following scheme:
- Psyche yearly MK files
psyche_YYYY_vVV.tm
when
YYYY is the year covered by the kernels listed in
the MK
VV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions.
Multiple versions of a meta-kernel for the same year may exist if
new kernels were added to the archive in a later release and the
meta-kernel for that year had to be updated to incorporate them. The
reasons for adding new kernels include (but are not limited to)
adding new kinds of kernels, adding new versions of existing kernels
containing more complete or more accurate data, and adding new
versions of existing kernels superseding the existing kernels that
had errors. If more than one meta-kernel file for the same year is
present, then the file with the latest version number supersedes all
earlier versions. The latest yearly meta-kernels can be loaded
together sorted by year to provide coverage for more than one year.
(Note that on some environments loading too many kernels at once may
slow down data access.)
Although the meta-kernels were created such that on a UNIX
workstation they can be loaded into a SPICE-based application
directly from the directory in which they reside -- because the
PATH_VALUES keyword is set to '..' and '/' is used as the path
delimiter -- it is recommended that users make local copies of these
files and update the PATH_VALUES keyword in each of them to point to
the actual location of the archive's 'spice_kernels' directory on
their system. Additional changes including replacing '/' and '\' in
all path specifications and converting UNIX line terminators to
terminators native to the user's system may be required to use these
meta-kernels on non-UNIX workstation.
The following guidelines were followed to pick and set priority --
determined by the order in which the kernel files are listed, with
the latest one taking precedence -- for the kernel files included in
these meta-kernels:
- the latest archived versions of LSK, PCK, SCLK, IK, FK, generic
SPKs
- the latest Psyche NAV SPKs were included
- the latest reconstructed CKs were included
Additional description of the kernels sets listed in a text MK file is
provided in metadata included inside the description area of the
file. This information can be viewed using any text editor program.
Back to Table of Contents
Miscellaneous Files
===================
Miscellaneous files provide value added elements that are outside the
scope of the PDS archive requirements. Miscellaneous files included in
this archive are currently limited to checksum files.
The subsection below provides details for these files.
Back to Table of Contents
Checksum Files
A checksum file provides a table of MD5 checksums for all files in the
archive as of a particular archive (bundle) version, including
checksums for all previous checksums files and their labels but
excluding the checksum for the checksum file itself and its label.
The checksum files are provided under the miscellaneous/checksum
directory and are named according to the following scheme:
- Psyche checksum files
checksum_vVVV.tab
where
VVV is the version; the file with the latest
version supersedes all similarly named
files with earlier versions and can be
used to validate the archive in its
entirety.
Back to Table of Contents
File Formats
============
All text documents, checksum files, and other meta information files
such as descriptions, detached PDS4 labels, and inventory tables, are
stream format files, with a carriage return (ASCII 13) and a line feed
character (ASCII 10) at the end of the records. This allows the files
to be read by most operating systems.
The text kernel files in this archive -- LSKs, PCKs, SCLKs, IKs, FKs,
and MKs -- are UNIX text files, with a line feed character (ASCII 10)
at the end of the line, and binary kernel files -- SPKs and CKs -- are
IEEE LSB binary files. While data files in this archive can be used
'as is' with SPICE toolkits for the majority of supported environments,
converting the files to the binary or text format native to the user's
computer may be required for use of the data with FORTRAN toolkits on
incompatible environments. Refer to the documentation provided with the
SPICE Toolkit to find out whether conversion is needed in each specific
case.
NAIF provides a tool (BINGO) that can convert either binary or text
kernels from one format to another. This means that text files can
have their line terminator changed and binary files can be converted
to the native format of the platform of interest. BINGO is available
from the utilities page at the NAIF Node of the PDS:
https://naif.jpl.nasa.gov/naif/utilities.html
Back to Table of Contents
SPICE Software and Documentation
================================
The latest SPICE Toolkit for a variety of computer platforms,
additional utility programs, documentation, tutorials, and hands-on
lessons are available at the NAIF Node of the PDS:
https://naif.jpl.nasa.gov
specifically:
Toolkit: https://naif.jpl.nasa.gov/naif/toolkit.html
Utilities: https://naif.jpl.nasa.gov/naif/utilities.html
Tutorials: https://naif.jpl.nasa.gov/naif/tutorials.html
Lessons: https://naif.jpl.nasa.gov/naif/lessons.html
Back to Table of Contents
Contact Information
===============================
PDS Navigation and Ancillary Information Facility (NAIF),
MAIL STOP 301-121
Jet Propulsion Laboratory
California Institute of Technology
4800 Oak Grove Drive
Pasadena, CA, 91109-8099
818-354-8136
WWW Site: https://naif.jpl.nasa.gov
Back to Table of Contents
Cognizant Persons
=================
This archive was produced by Alyssa Bailey, Matt Barnes, and Boris Semenov,
Planetary Data System Navigation and Ancillary Information Facility
Node, Jet Propulsion Laboratory, Pasadena, California.
End of Psyche SPICE archive description.
Back to Table of Contents